Intelligent monitoring systems for liquid electrolyte batteries

ABSTRACT

An improved battery monitoring system for liquid electrolyte batteries is provided. The battery monitoring system includes a network of sensors for monitoring the condition or performance of a plurality of liquid electrolyte batteries, for example lead-acid batteries. The sensors are adapted to share data regarding battery condition or battery performance to a standalone device over a wireless local area network. A server in electrical communication with the standalone device receives some or all of the data for analysis, which can result in maintenance alerts and other alerts being sent to the standalone device. The improved battery monitoring system can reduce or eliminate the manual inspection of lead-acid batteries and can improve battery operation and longevity by ensuring an appropriate level of maintenance for each lead-acid battery.

FIELD OF THE INVENTION

The present invention relates to intelligent systems for monitoring thecondition and performance of liquid electrolyte batteries, for examplelead-acid batteries.

BACKGROUND OF THE INVENTION

Liquid electrolyte batteries, for example lead-acid batteries, provideelectrical energy by means of an electrochemical reaction. Theelectrochemical reaction involves the reaction of an acid, for examplesulfuric acid, with a battery electrode to create an electricalpotential. Owing to their reliability and low cost, lead-acid batteriesare among the primary sources of electrical power for self-poweredvehicles (including for example forklifts and reach trucks), standbypower and other applications.

A variety of sensors exist for monitoring the condition or performanceof lead-acid batteries. For example, lead-acid batteries experience aloss of water when recharging and from heat induced water evaporation.Accordingly, known water level sensors can measure the liquid levelwithin the battery enclosure. Additional sensors are known to measureambient air temperature, battery fluid temperature, battery voltage,amp-hour throughput, and half-voltage (the voltage of one half of thebattery as compared to the other half of the battery).

A variety of issues arise with existing sensors, however. For example,existing sensors lack integration, and do not entirely mitigate the needto manually inspect each battery. In addition, existing liquid levelsensors do not measure the amount of water consumed by the battery, andinstead measure the presence or absence of a predetermined liquid levelat a given point in time.

Accordingly, there remains a continued need for an improved batterymonitoring system for liquid electrolyte batteries, and in particularlead-acid batteries. In addition, there remains a continued need for animproved battery monitoring system that automatically monitors thecondition and performance of lead-acid batteries to thereby improvebattery operation and longevity.

SUMMARY OF THE INVENTION

A battery monitoring system for a plurality of liquid electrolytebatteries is provided. The battery monitoring system includes a networkof sensors for monitoring the condition or performance of each of theplurality of batteries. Sensor data from the network of sensors isshared with a standalone device over a wireless network. The standalonedevice, for example a smartphone or a tablet, communicates with a serverfor analysis of the sensor data. The standalone device providesmaintenance alerts to ensure the proper care and maintenance of theplurality of batteries.

In one embodiment, each of the plurality of batteries includes a controlmodule in electrical communication with the network of sensors. Thesensors can include a voltage sensor, a flow rate sensor, a pressuresensor, a liquid level sensor, an amp-hour throughput current sensor,and a dirty battery sensor. The control module additionally includes anon-board temperature sensor and an on-board accelerometer. The sensorsmeasure the electrolyte liquid level, the electrolyte liquidtemperature, the ambient temperature, the battery orientation, theamp-hour throughput, the voltage between positive and negativeterminals, and the half voltage of the battery.

In another embodiment, the control module shares data over the wirelessnetwork, optionally in accordance with the Bluetooth Smart advertisingmode. The first packet relates to battery status. The battery statuspacket can alert the user if a battery requires immediate attention. Forexample, the battery status packet can contain information relating tobattery impacts, battery temperature, cell imbalance, and lowelectrolyte levels. The second packet includes historical sensor data,the historical sensor data including a digital timestamp. The historicalsensor data is forwarded to the server for storage and analysis.

In still another embodiment, the control module shares data with thestandalone device over a wireless personal area network, for example aBluetooth Smart network or a ZigBee network. The standalone device caninclude a smartphone, a tablet, a laptop computer, a desktop computer,or a vehicle computer adapted to receive data over the wireless personalarea network. The standalone device can also include a gateway (wirelessaccess point), a cellular system, or a mesh network. The standalonedevice includes an application program adapted to display maintenancealerts or other alerts, indicating for example an unsafe liquid level oran unsafe battery temperature.

In even another embodiment, the battery monitoring system measures theamount of water added to a lead-acid battery. The battery monitoringsystem includes a flow rate sensor, a pressure sensor, and amicroprocessor coupled to the output of the flow rate sensor and thepressure sensor. The microprocessor determines the amount of water addedto the lead-acid battery based on the measured pressure within a feedtube when the flow rate exceeds a predetermined minimum flow-rate. Theamount of water added to the battery can indicate the condition of thebattery and its remaining useful life.

In yet another embodiment, the battery monitoring system measures theamount of water added to a lead-acid battery without a flow-rate sensor.In this embodiment, the microprocessor determines the amount of wateradded to the lead-acid battery based on the period of time between whenthe water pressure exceeds a minimum pressure and when the waterpressure stabilizes at a maximum pressure. As noted above, the amount ofwater added to the battery can indicate the condition of the battery andits remaining useful life.

In still another embodiment, the battery monitoring system determines ifwater was added to a lead-acid battery using a pressure sensor,optionally without a flow-rate sensor. In this embodiment, themicroprocessor measures the output of the pressure sensor to determineif a battery has been watered. If the battery has not been watered, theuser can be alerted to the need to water the battery, optionally throughmaintenance alerts published to the standalone device.

In even another embodiment, the battery monitoring system includes amulti-axis accelerometer, a microprocessor coupled to the output of theaccelerometer, and a standalone unit in wireless communication with themicroprocessor. The microprocessor is operable to determine an impact tothe battery housing and an orientation of the battery housing based onthe accelerometer output. This information is broadcast to thestandalone device. The standalone device can alert a user of an unsafebattery condition, for example a battery housing being in an unsafeorientation (e.g., severely tilted) or a battery housing that wassubject to an unsafe impact (e.g., dropped).

The present invention can therefore provide an improved batterymonitoring system for liquid electrolyte batteries, and in particularlead-acid batteries. The improved battery monitoring system can replaceexisting sensors with a network of connected sensors to provide analysisof battery performance and battery condition. The improved batterymonitoring system can reduce or eliminate the manual inspection oflead-acid batteries and can improve battery operation and longevity byensuring an appropriate level of maintenance for each lead-acid battery.

These and other features and advantages of the present invention willbecome apparent from the following description of the invention, whenviewed in accordance with the accompanying drawings and appended claims.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a deep cycle lead-acid battery coupledto a single point watering system.

FIG. 2 is a top plan view of a deep cycle lead-acid battery coupled to asingle point watering system.

FIG. 3 is a top plan view of a battery monitoring system in accordancewith a current embodiment.

FIG. 4 is a perspective view of a control module with internal wirelesscommunications circuitry in accordance with a current embodiment.

FIG. 5 is a schematic diagram of the control module in accordance with acurrent embodiment.

FIG. 6 is an illustration of a battery monitoring system including ahandheld device and a remote server for determining battery alerts.

FIG. 7 is a flow chart illustrating the collection of sensor data inaccordance with a current embodiment.

FIG. 8 is a flow chart illustrating the uploading of sensor data from aplurality of control modules to a local standalone device.

FIG. 9 is a flow chart illustrating the uploading of sensor data from alocal standalone device to a remote server.

FIG. 10 is a flow chart illustrating the evaluation of accelerometerdata for a battery in accordance with a current embodiment.

DETAILED DESCRIPTION OF THE CURRENT EMBODIMENTS

The invention as contemplated and disclosed herein includes a batterymonitoring system for liquid electrolyte batteries, and in particularlead-acid batteries. As set forth below, the battery monitoring systemincludes a network of sensors for monitoring the condition orperformance of a plurality of liquid electrolyte batteries. The sensordata is shared with a standalone device over a wireless network. Aserver in electrical communication with the standalone device receivesthe data for analysis, which can result in additional maintenance alertsand other alerts being sent to the standalone device.

I. Battery Overview

Referring now to FIG. 1, an exemplary liquid electrolyte battery isillustrated and generally designated 100. The liquid electrolyte battery100 is a deep cycle lead-acid battery including multiple battery cellsthat house an assembly of electrodes, electrolyte solution, andterminals. The battery cells share a common housing 102, and include a12 volt construction. Each battery cell includes a small vent opening onthe housing cover 104. The lead-acid battery also includes vent capsthat are twisted into the vent openings for each battery cell. Positiveand negative terminals 106, 108 protrude from the top of the housingcover 104.

During recharging, and due to heat induced water evaporation, thelead-acid battery 100 will experience a loss of water. As shown in FIG.1, a single point watering system 110 provides water to each batterycell. The single point watering system includes a flexible feed tube 116that provides a fluid flow path from an inlet 112 to each battery cell.The single point watering system also includes a refill control valve114 for each battery cell, replacing the vent caps and being twistedinto the vent openings for each battery cell.

II. System Overview

As noted above, the current embodiments include a battery monitoringsystem for monitoring the condition or performance of a plurality ofdeep cycle lead-acid batteries. The battery monitoring system 10 isshown in FIGS. 1-5 and includes a control module 12, a plurality ofexternal sensors, and a plurality of internal sensors. The externalsensors include a current sensor 14, a flow rate sensor 16, a pressuresensor 18, a positive electrode 20, a ground electrode 22, a halfvoltage electrode 24, a liquid level sensor 28, and a dirty batterysensor 30. The internal sensors (internal to the control module 12)include a temperature sensor 32 and an accelerometer 34. Otherembodiments include greater or fewer number of external sensors and/orinternal sensors as required. Each sensor measures a characteristic(e.g., condition or performance) of the lead-acid battery 100. Themeasured characteristic can include the electrolyte liquid level, theelectrolyte liquid temperature, the ambient temperature, the housingintegrity (e.g., any history of past drops or impacts), the housingorientation, the voltage between positive and negative terminals, andthe half voltage of the battery 100. Other characteristics can bemeasured in other embodiments as desired.

As shown in FIGS. 1-2, the control module 12 is centrally mounted to thehousing cover 104. The control module 12 includes an internal controllerfor processing the output of the sensors noted above. The controller isa microprocessor 40 in the present embodiment, but can include anapplication specific integrated circuit (ASIC) or a field programmablegate array (FPGA) in other embodiments, for example. The microprocessor40 is coupled to output of each sensor identified above, optionallythrough an analog to digital converter (ADC) 42. The control module 12can additionally include a shift register, for example parallel-in,serial-out shift register to reduce the number of inputs to themicroprocessor 40. The shift register can be incorporated into thesignal conditioning circuit 44, shown in FIG. 5 as being connectedbetween the external sensors and the microprocessor 40. Themicroprocessor 40 can additionally include an integrated communicationscircuit for communication over a wireless personal area network, forexample a Bluetooth Smart (BLE) network. Other networks include ZigBeenetworks and Wi-Fi networks, for example. Where a Bluetooth Smartnetwork is used, the integrated communications circuit can include aBluetooth chip and integral 2.4 GHz antenna for communication with astandalone device (discussed below).

As also shown in FIG. 5, the control module 12 includes a programminginterface 46, a serial debugger interface 48, an on-board temperaturesensor 32, on-board accelerometer 34, external non-volatile memory (NVM)50, on-board LED indicators 52, a serial bus to remote LED indicators54, a regulated rail voltage 56, and a four-pin wire-to-wire connector58. The programming interface 46 receives computer readable instructionsfor processing the sensor data and/or broadcasting the sensor data overthe wireless network. The serial debugger interface 48 supports datatransfer to verify the microprocessor 40 is working properly beforepackaging and shipment. The on-board temperature sensor 32 provides atemperature measurement for output to the microprocessor 40. Thetemperature sensor 32 can include a thermistor having a variableresistance. By measuring the resistance of the thermistor, optionallyusing a voltage divider, the microprocessor 40 can determine the ambientair temperature. The on-board accelerometer 34 is a three-axisaccelerometer to measure the orientation of the battery 100 (e.g.,upright, inverted, tilted) and any impacts to the battery 100. Theon-board LED indicators 52 provide immediate feedback regarding thecondition or performance of the battery 100. In some embodiments, theon-board indicators 52 include three LEDs: a steady green LED, a steadyred LED, and a flashing red LED. The steady green LED can indicate theliquid level does not need refilling, the flashing red can indicate theliquid level needs refilling, and the steady red can indicate the liquidlevel is too high. Though described as being present on the controlmodule 12, the LED indicators 52 can also or alternatively be presentelsewhere, for example on the liquid level sensor 28. The LED indicators42 can alternatively be present at the end of a wire protruding from thecontrol module 12. Lastly, the wire-to-wire connector 58 includes fourconnections in the present embodiment, two to the microcontroller (5Vand ground) and two to the serial debugger interface 48 (transfer andreceive).

Periodically or as the sensor data is collected, the control module 12publishes or transmits the sensor data over the wireless network for anearby standalone device 60. The standalone device 60 includes ahandheld device, for example a smartphone, a tablet, or a laptop, orincludes a desktop device, for example a computer workstation, or acomponent of a vehicle, for example an on-board vehicle computer. Thestandalone device 60 then communicates all or a portion of the data to aremote server 62 for further analysis. As shown in FIG. 6, thestandalone device 60 can be connected to a plurality of batterymonitoring systems 10 over the wireless network. The data transmitted tothe remote server 62 can be stored in a remote database and/or analyzed.For example, the remote server 62 can analyze the sensor data andcommunicate added maintenance alerts and other alerts to the standalonedevice 62.

To reiterate, the standalone device 60 acquires sensor data from aplurality of control modules 12, each associated with a battery 100. Inone embodiment, the control modules 12 communicate with the standalonedevice 60 according to the Bluetooth Smart protocol (also calledBluetooth Low Energy, Bluetooth LE, or BLE). According to the BluetoothSmart protocol, the control modules 12 are each a peripheral device thatposts data for a central device to read. The standalone device 60, as acentral device, reads the published data from the control modules 12.The control modules 12 can update the published data regularly or inresponse to an event, for example when there is a significant change tothe sensor data. The sensor data includes two packets. The first packetincludes battery status. The battery status packet can be used to alertthe user that the battery requires an action item. For example, thebattery status packet can contain information relating to batteryimpacts, over temperature, cell imbalance, and low electrolyte levels.The action item can include refilling the battery with water, replacingthe battery with a new battery, cleaning the battery top cover, orreturning the battery to an upright orientation. The action item canalso include equalization, charging a battery, repairing a battery,temperature single point watering system repair, or state of charge. Theaction items can be presented to the user on a touch screen display ofthe standalone device 62, for example. The second packet can includehistorical sensor data, the historical sensor data including a digitaltimestamp for diagnostic analysis by the remote server 62 as explainedfurther below.

More particularly, the remote server 62 includes a processor to executea series of diagnostic functions relative to the batteries 100. Based onthe output of the diagnostic functions, the remote server 62 transmitsone or more maintenance alerts to the standalone device 60. In otherembodiments, however, the standalone device 60 includes an internalprocessor adapted to execute the diagnostic functions relative to thebatteries 100. In these embodiments, the remote server 62 is omitted,and the standalone device 60 provides self-alerts. The diagnosticfunctions include a series of instructions stored in a computer readabledata storage device. The computer readable data storage device can be aportable memory device that is readable by a processor. Such portablememory devices can include a compact disk, a digital video disk, a flashdrive, and any other disk readable by a disk driver embedded orexternally connected to a computer, a memory stick, or any otherportable storage medium whether now known or hereinafter developed.Alternatively, the machine-readable data storage device can be anembedded component of a computer such as a hard disk or a flash drive ofa computer.

III. Sensor Overview

As noted above, the battery monitoring system 10 includes a variety ofsensors for measuring and reporting one or more characteristics of thebattery 100. Exemplary sensors are discussed below by non-limitingexample; additional sensors can be utilized in other embodiments asdesired. The sensor data is time stamped and analyzed by themicrocontroller 40 before being broadcast over the wireless network.

The current sensor 14 is an electrical sensor adapted to measure thepower output of the battery 100. As shown in FIG. 5, the current sensor14 is coupled to the signal conditioning circuit 44 with two inputs(supply and ground) and one output (current sensor signal). The analogvalue of the signal is proportional to the power output of the battery100, and is output to the microprocessor 40 as an analog input.

The flow sensor 16 is an in-line flow sensor having an inlet and anoutlet in fluid communication with the feed tube 116. The flow sensor 16includes an internal rotor and an internal hall-effect sensor. The speedat which the rotor spins will vary in dependence on the water flow rate.The hall-effect sensor outputs a corresponding pulse signal to thesignal conditioning circuit 44, which in turns outputs to themicroprocessor 40 through an ADC 42. The microprocessor 40 then convertsthe digital signal to a value corresponding to the flow rate within thefeed tube 116.

The pressure sensor 18 is an in-line pressure sensor having an inlet andan outlet in fluid communication with the feed tube 116. The pressuresensor 18 outputs an analog signal in proportion to the fluid pressurein the feed tube 116. The output of the pressure sensor 18 is coupled tothe signal conditioning circuit 44, which in turns outputs to themicroprocessor 40 through an ADC 42. The microprocessor 40 then convertsthe digital signal to a value corresponding to the pressure within thefeed tube 116.

The half voltage sensor 24 is adapted to compare the voltage at one halfof the battery 100 against the voltage at the other half of the battery100. As shown in FIG. 5, the half voltage sensor 24 includes an outputto the signal conditioning unit 44, the output being between 4 and 46volts DC. The half battery voltage is one of four inputs into the ADC42, which also includes each terminal voltage (represented by BATT+ andBATT−) and the dirty battery voltage.

The liquid level sensor 28 includes a capacitive sensor that measuresthe liquid level within the battery housing 104. The capacitive sensorprovides an output that varies as the liquid level increases in relationto the probe. The output of the liquid level sensor 28 is coupled to thewire-to-wire connector 58 and subsequently the microprocessor 40. Thestructure and functionality of the liquid level sensor 28 are set forthin U.S. application Ser. No. ______ entitled “Liquid Level Sensor forBattery Monitoring Systems,” filed on even date herewith, the contentsof which are incorporated by reference in their entirety.

The dirty battery sensor 30 detects the accumulation of electrolyte onthe battery cover 104, and includes a conductive pad on the batterycover 104. The conductive pad outputs a voltage to the signalconditioning circuit 44, shown in FIG. 5 as the “dirty battery voltage.”The ADC 42 outputs a digital signal to the microprocessor 40, thedigital signal being based on the dirty battery voltage. Once thevoltage between the negative terminal 22 and the conductive pad fallswithin a predetermined range, a short is present on the battery cover104, and a signal can be sent to the standalone unit 60 to notify theend user that the battery cover 104 should be cleaned.

The on-board temperature sensor 32 provides a temperature measurementabove the water level (e.g., atop the battery cover 104) for output tothe microprocessor 40. The on-board temperature sensor 32 includes athermistor in the present embodiment, the thermistor having a resistancein proportion to the ambient temperature. The output of the on-boardtemperature sensor 32 is an analog input to the microprocessor 40.

The on-board accelerometer 34 is a three-axis accelerometer thatprovides orientation sensing, free fall sensing, and impact sensing.More particularly, the on-board accelerometer 34 measures theorientation of the battery 100 (e.g., upright, inverted, tilted) and anyfree fall events or impacts to the battery 100. The output of theon-board temperature sensor 32 is an analog input to the microprocessor40.

With reference to FIG. 7, a flow chart depicting operation of the sensordata is depicted. At decision step 70, the microprocessor 40 determinesif the present iteration follows from a boot-up or a power cycle. If apower cycle is detected, the microcontroller sets a flag for loss ofpower in non-volatile memory 50 at step 72 for later transmission to thestandalone device 60. If a boot-up is detected, the microprocessor 40initiates watchdog timers for sampling the sensor data, transmittingover the wireless network, and polling the onboard sensors at step 74.As used herein, watchdog timers include an electronic countdown timerthat regularly restarts during normal operation. At decision step 76,the microprocessor 40 determines if an interrupt is triggered. If aninterrupt is triggered, the microprocessor 40 identifies the interruptas being from the accelerometer or communications circuit at step 78.The microprocessor 40 reads the accelerometer 34 at step 80 or servicesthe communications request at step 82 depending on the outcome ofdecision step 78. At decision step 84, the microprocessor 40 determinesif a timeout has expired. If not, the microprocessor 40 returns to step74. If a timeout has expired, the microprocessor 40 identifies thesource of the timeout at decision step 86. The microprocessor 40 thenreads the sensor data in accordance with the source of the timeout, andthereafter returns to step 74. In the absence of any timeouts, themicroprocessor 40 stores sensor data to non-volatile memory 50 forcomparison against threshold values also stored to non-volatile memory50. The threshold values can be updated from time to time by thestandalone device 60. Sensor data that is outside of expected parametersis timestamped and stored to non-volatile memory 50 for broadcast overthe wireless network, optionally the Bluetooth LE wireless personal areanetwork.

The reading of data by the standalone device 60 is further illustratedin FIG. 8. At step 90, and after discovering each control module 12 onthe local wireless network, the standalone device 60 identifies eachcontrol module 12 (identified as a “peripheral device” or “peripheral”in FIGS. 8 and 9). At step 92, the standalone device 60 connects withand authenticates each such control module 12. The standalone device 60reads data from each such control module 12 at step 94 and writes thedata to local memory at step 96. The standalone device 60 determines ifthe data read is complete at step 98. If the data read is not complete,the standalone device 60 continues to look for data packets from thecontrol modules 12 at step 100. If the data read is complete, thestandalone device 60 disconnects from the control modules 12 at step102. If a wireless network is available at step 104, the standalonedevice 60 uploads the data to the remote server 62 at step 106. Atdecision step 108, the standalone device 60 determines if the data readis complete, and if not, returns to step 90 for a further iteration.

The uploading of data from the standalone device 60 to the server 62 isfurther illustrated in FIG. 9. At step 110, the standalone device 60determines if a wireless network is available. If no wireless network isavailable, the standalone device 60 continues with attempts to connectto a wireless network at step 112. If a wireless network is available,the standalone device 60 authenticates to the server applicationprogramming interface (API) at step 114. At step 116, the standalonedevice 60 checks the time of the last update. At step 118, thestandalone device 60 filters its local storage for data received fromthe control modules 12 since the last server upload. At step 120, thestandalone device 60 transmits a POST request to the server 62,requesting that the server 62 accept and store data accompanying thePOST request, the data corresponding to timestamped sensor data from thecontrol modules 12. At step 122, the standalone device 60 receives aresponse code and message from the server 62. At step 124, thestandalone device 60 determines if the request was received by theserver 62 and is being processed, e.g., response code 200 in HTML. Thestandalone device 60 repeats or terminates the above process dependingupon whether receipt of the POST request was acknowledged by the server62.

IV. Diagnostic Functions

As noted above, the battery monitoring system 10 is adapted to provideautomated diagnostics for the plurality of lead-acid batteries 100. Theautomated diagnostics can result in maintenance alerts to ensure theproper care and maintenance of each of the plurality of lead-acidbatteries 100. The diagnostics can be performed remotely by the controlmodule microprocessor 40 in some embodiments, while in other embodimentsthe diagnostics can be performed locally by the standalone device 60 orby the server 62. The resulting maintenance alerts are then presented byan application program hosted on the standalone device 60 for viewing bythe user.

In accordance with the current embodiments, a number of diagnosticfunctions are presented below. These diagnostic functions include: (a)measuring the liquid level within each of the plurality of batteries;(b) measuring the volume of water added to each of the plurality ofbatteries using a flow rate sensor and a pressure sensor; (c) measuringthe volume of water added to each of the plurality of batteries using apressure sensor but not a flow-rate sensor; and (d) measuring theorientation of the batteries and any unsafe impacts using anaccelerometer. Additional diagnostic functions can be utilized in otherembodiments as desired. The output of each diagnostic function generallyincludes an alert to the standalone device to indicate an action itemwith respect to a battery. The action item can include refilling thebattery with water, replacing the battery with a new battery, cleaningthe battery top cover, or returning the battery to an uprightorientation. Other alerts can be generated in other embodiments asdesired.

Measuring the liquid level within the batteries generally includesmeasuring the output of the liquid level sensor 28 and comparing theoutput against a predetermined minimum liquid level. The output of theliquid level sensor 28 varies in relation to the liquid level within thebattery, such that a plurality of non-zero liquid levels can bedetected. If the comparison (performed by the microprocessor 40, thestandalone device 60, or the server 62) determines that the measuredliquid level is below the minimum liquid level, the standalone device 60generates an alert to the user. The alert can include an action item torefill the battery prior to its next use. The action item can bepresented on an application program hosted on the standalone device 60.

Measuring the volume of water added to the batteries generally includes(for each battery) measuring the flow rate of water moving through thefeed tube 116, calculating the volume of water added during the periodin which the measured flow rate exceeded a minimum flow rate, outputtingthe calculated water volume for an application program hosted on thestandalone device 60, and optionally indicating to the user of thestandalone device 60 when the watering is complete. Calculating thevolume of water added is performed by multiplying the flow rate (asderived from the output of the flow rate sensor 16) by the area of thefeed tube 116 to determine the volumetric flow rate. The volumetric flowrate is then multiplied by the total time period in which flow rateexceeded a minimum flow rate, arriving at the measured volume of wateradded, also referred to as the “refilling volume” herein. If the flowrate is not steady, the above calculation can be performed byintegrating the flow-rate over the same period. The measured volume ofwater added is then compared with an expected volume of water added forthat particular battery. The expected volume of water added can be afunction of the remaining useful life of the battery, which in turn canbe based on the previous number of charges, for example. If the measuredvolume of water added exceeds the expected volume of water added, thestandalone device 60 generates an alert to the user. The alert caninclude an action item to replace the aging battery. The action item canbe displayed by an application program hosted on the standalone device60. The standalone device 60 can additionally schedule water refillingsbased on the collected data.

Measuring the volume of water added to the batteries can alternativelyinclude (for each battery) measuring the pressure of water movingthrough the feed tube 116, calculating the volume of water added duringthe period in which the measured pressure is between a minimum pressureand a maximum pressure, outputting the calculated water volume for anapplication program hosted on the standalone device 60, and indicatingto the user of the standalone device when the watering is complete.Calculating the volume of water added is performed according toBernoulli's equation in which the flow rate is derived from the pressurewithin the feed tube 116 (as measured by the pressure sensor 18). Theflow rate is then multiplied by the area of the feed tube 116 todetermine the volumetric flow rate. The volumetric flow rate is thenmultiplied by the total time period in which the measured pressure wasbetween a predetermined minimum pressure and a predetermined maximumpressure, arriving at the refilling volume. If the flow rate is notsteady, the above calculation can be performed by integrating theflow-rate over the same period. The refilling volume is then comparedwith an expected volume of water added for that particular battery. Theexpected volume of water added can be a function of the remaining usefullife of the battery, which in turn can be based on the previous numberof charges, for example. If the refilling volume exceeds the expectedvolume of water added, the standalone device 60 generates an alert tothe user. The alert can include an action item to replace the agingbattery. The action item can be displayed by an application programhosted on the standalone device 60. The standalone device 60 canadditionally schedule water refillings based on the collected data. Insome embodiments, this method is modified to detect whether the batterywas watered, independent of a measurement of the amount of water addedto the battery. For example, this method can include a determination ofwhether the battery was watered based on a comparison of the measuredpressure (or the flow rate as derived above) with a threshold pressure(or a threshold flow rate). If the battery has not been watered, thestandalone device 60 generates an alert to the user. The alert caninclude an action item to water the battery. The action item can bedisplayed by an application program hosted on the standalone device 60.

Measuring the orientation of the batteries and any unsafe impactsincludes (for each battery) measuring the accelerometer output anddetermining, based on the accelerometer output, the orientation of thebattery housing and any impacts thereto. The orientation of the batteryhousing can be compared with an acceptable range of orientations storedto computer readable memory. If the measured orientation is outside theaccepted range of orientations, the standalone device 60 generates analert to the user. The alert can include an action item to return thebattery to its upright position. The action item can be presented on anapplication program hosted on the standalone device 60. If theaccelerometer output reveals any g-forces in excess of a predeterminedmaximum g-force, the standalone device 60 generates an alert to theuser. The alert can include an action item to visually inspect orreplace the battery. The action item can be presented on an applicationprogram hosted on the standalone device 60.

Further with respect to FIG. 10, measuring the orientation of thebatteries and any unsafe impacts includes reading the accelerometercount data over a 12C-Bus at step 130. The accelerometer data isanalyzed at step 132 for angle events and impact events. At decisionstep 134, the microcontroller determines if the accelerometer datarelates to an angle event, an impact event, or both events. If an angleevent is determined, the microprocessor 60 sets an exception flag forthe angle event to be used by a Bluetooth LE advertising packet at step136. This data is stored to NVM 50 with a timestamp at step 138. If animpact event is determined, the microprocessor 60 sets an exception flagfor the impact event to be used by a Bluetooth LE advertising packet atstep 140. This data is stored to NVM 50 with a timestamp at step 142. Ifboth events are determined, the microprocessor 60 sets an exception flagfor both events to be used by a Bluetooth LE advertising packet at step144. This data is stored to NVM 50 with a timestamp at step 146. Thestored data is later transmitted across the Bluetooth LE network forreceipt by the standalone device 60 at step 130.

The application program for the standalone device 60 can thereforepresent a number of maintenance alerts pertaining to a plurality ofbatteries. The maintenance alerts can indicate a battery conditionand/or an action item with respect to the battery. The action item caninclude a recommendation to visual inspecting the battery housing forcracks, refill the battery with water, replace the battery with a newbattery, clean the battery top cover, or return the battery to anupright orientation. Other alerts can be generated in other embodimentsas desired. The application program can also receive inputs from theuser. For example, the application program can receive confirmation thatthe action item was performed, e.g., the battery was inspected, thebattery was refilled with water, the battery was replaced, the batterywas cleaned, or the battery was returned to an upright orientation. Theinput can be transmitted to one or both of the microcontroller 40 or theremote server 62.

The above description is that of current embodiments of the invention.Various alterations and changes can be made without departing from thespirit and broader aspects of the invention as defined in the appendedclaims, which are to be interpreted in accordance with the principles ofpatent law including the doctrine of equivalents. Any reference toelements in the singular, for example, using the articles “a,” “an,”“the,” or “said,” is not to be construed as limiting the element to thesingular.

1. A battery monitoring system for a liquid electrolyte battery, thebattery monitoring system comprising: a battery monitoring unitincluding a control module and a plurality of sensors, wherein thebattery monitoring unit is joined to the liquid electrolyte battery; alocal standalone device in communication with the control module for thebattery monitoring unit over a network; and a remote server incommunication with the standalone device, wherein the server receivessensor data from the standalone device for the liquid electrolytebattery, and wherein the remote server performs an analysis of thesensor data and transmits a battery notification to the standalonedevice.
 2. The battery monitoring system of claim 1 wherein the controlmodule includes a communications circuit for transmitting over thenetwork, the network being a wireless personal area network.
 3. Thebattery monitoring system of claim 1 wherein the sensor data relates tobattery liquid level, battery refilling volume, battery half voltage, orbattery orientation.
 4. The battery monitoring system of claim 1 whereinthe plurality of sensors includes an accelerometer, a liquid levelsensor, a flow rate sensor, a pressure sensor, a temperature sensor, ora dirty battery sensor.
 5. The battery monitoring system of claim 1wherein the battery notification indicates a recommended action itemincluding refilling a battery, replacing a battery, inspecting abattery, returning a battery to an upright orientation, equalization,charging a battery, repairing a battery, temperature single pointwatering system repair, or state of charge.
 6. A battery monitoringsystem for a liquid electrolyte battery having a battery housing, thebattery monitoring system comprising: a control module joined to thebattery housing and including: a multi-axis accelerometer, themulti-axis accelerometer providing an output, and a controllerelectrically coupled to the accelerometer output, the controller beingoperable to determine an impact to the battery housing and anorientation of the battery housing based on the accelerometer output. 7.The battery monitoring system of claim 6 further including a standalonedevice in electrical communication with the controller over a wirelessnetwork, wherein the controller is adapted to output battery impact dataand battery orientation data to the standalone device over the wirelessnetwork to alert a user of an unsafe battery condition.
 8. The batterymonitoring system of claim 7 wherein the unsafe battery conditionindicates the battery housing includes an unsafe orientation or wassubject to a predetermined impact.
 9. The battery monitoring system ofclaim 7 wherein the controller includes an integrated communicationscircuit for sharing data over the wireless network.